Sputtering is a physical vapor deposition (PVD) method of depositing thin films by ejecting, material from a “target,” that is source. This material is then deposited onto a “substrate,” such as a semiconductor wafer.
Sputtering sources use strong electric and magnetic fields to trap electrons close to the surface of the target. The electrons follow helical paths around the magnetic field lines and collide with the target surface, transferring kinetic energy to particles that are ejected from the target towards the substrate. Sputtering can be performed at a lower temperature than a melting temperature of the target material.
Sputtering has been considered for use in fabricating thin film photovoltaic solar cells. Because the solar panels occupy a large substrate area, maintaining thickness uniformity throughout the length and width of a thin film solar panel is a challenge.